Brain Storm

You must have an Intelligence of 18 or higher to cast this spell. 

Project the thoughts out from the brain to create a brain storm centered on the brain used to cast this spell. Until the spell ends, a 30-foot-radius, 40-foot-high cylinder of a Lightning Storm is centered on the brain. When the cylinder appears, each creature in it must make a Dexterity saving throw, taking 4d10 Lightning or Thunder damage (Your choice when casting the spell) on a failed save, or half as much damage on a successful one.You may exempt a number of creatures equal to your intelligence modifier plus your proficiency modifier from the effects of this spell, including yourself. A creature must also make this saving throw whenever it ends its turn in the cylinder.

When you cast this spell at a level higher than 5th, the damage is does is increased by 1d10.